a) Will you provide support?
Yes, we will provide suport.
b) For which version this extension is compatible?
This extension is compatible with Magento 1.6.0, 1.6.1, 1.6.2 1.7 and 1.8.
c) Would it compatible with Magento Go?
No its only compatible with magento community version.
d) Is it works on third party theme?
Yes, it working good on third party theme.
e) Will I be able to add external links as a menu item to the top navigation bar?
Yes you will add it.
f) Can I add more than 1 product in mega menu?
Yes you can add it.